The major problem of developing pharmaceutical formulations of Ibuprofen is to address its poor solubility in water. Sodium dihydrate salt of Ibuprofen, the compound of Formula (Structure I), is an alkali metal salt of Ibuprofen which is freely soluble in water. Therefore, it is a good candidate for preparing a pharmaceutical formulation having better bioavailability. It is a very effective Non steroidal anti-inflammatory drug (NSAID), analgesic (pain reliever), and antipyretic (fever reducer). NSAID is the general term used for a group of drugs that are effective in reducing inflammation and pain.

Several processes are known for the preparation of Sodium dihydrate salt of Ibuprofen. The known processes include the method of producing Sodium dihydrate salt of Ibuprofen by using different base for treating with Ibuprofen, different organic solvents as reaction medium, different experimental parameters etc.
Japanese Patent No. 53044538 to Kiyaoura, et al., (Mitsui Toatsu Chemicals Inc., Japan) describes the preparation of sodium α-(4-isobutylphenyl) propionate by treating ibuprofen with a mixture of sodium hydroxide and 5% Pd/C in n-tetradecane by autoclaving at 200° C. for 1.5 hr. This method provides only sodium ibuprofen, which is not in hydrate form and is expensive due to the usage of Pd/C catalyst.
U.S. Pat. No. 4,859,704 to Haas, (Oratech Pharmaceutical Development Corporation, Princeton, N.J.) describes the method of making alkali metal salt of ibuprofen by treating ibuprofen with alkali metal carbonate in water media at an elevated temperature of 55–60° C. This method involves the evolution of CO2 gas, which may lead to pressurization inside the reactor. Although method is simple the pressurization due to the evolution of CO2 gas makes the process less attractive.
U.S. Pat. No. 5,969,181 to Breitenbach, et al., describes the method of preparing the sodium salt of ibuprofen racemate by reacting ibuprofen with sodium carbonate in the melt in an extruder. This method gives ibuprofen sodium without water of crystallization and also requires intermeshing twin screw extruder.
U.S. Pat. No. 6,525,214 to Armitage, et al., describes the preparation of pure enantiomeric salt of ibuprofen such as S(+)sodium 2-(4-isbutylphenyl) propionic acid dihydrate and S(−)sodium 2-(4-isbutylphenyl) propionic acid dihydrate by treating S(+)2-(4-isbutylphenyl) propionic acid [S(+)ibuprofen] and S(−)2-(4-isbutylphenyl) propionic acid [S(−)ibuprofen] with sodium hydroxide in aqueous media and the precipitation of the product in acetone.
The invention disclosed herein demonstrates simple, economical and a commercially viable process for producing Sodium dihydrate salt of Ibuprofen using suitable salt and solvents.